Spark-plug.



0. W. BECK. SPARK PLUG.- APPLICATION FILED MAR.17, 1910.

Patented Jan.20.1914

NIH

W/TNESSES:

failing to do'its work.

when STATES PATENT. OFFICE;

CHARLES 2v. BECK, or ROCKVILLE cnnrn'n, NEW ,Yonx, assxonon, BY MESNE ASSIGN- MENTS, TO MICHIGAN MOTOR srEcIaLrIns COMPANY, or DETROIT, MICHIGAN, A.

CORPORATION OF MICHIGAN.

srnmrrrue.

Specification of Letter P ten Patented Jan20,1914.

Application filed March 1 7, 1910. Serial No. 549,875.

To all whom it may concern Be it known that I, CHARLES W. BECK, a citizen of the United States,'andresident of Rockville Center, county of Nassamand State of New York, have invented certain new and useful Im )rovementsin Spark- Plugs, of which the ollowing is a specifica tion.

" In 'internalcombustion motors-with more than one cylinder it frequently happens that one or more of the cylinders do not properly work, that is to say, thefmixturetherein is not ignited. It is always .ditlicultto determine, in cases of this kind, which cylinder is not working, thatis to say, i'n which cylinder the, mixture isnot ignited.

Various devices are used-for vdetermining whether electric" current is being supplied to the spark plugs, but sofar as I am aware, 3 there are no dev ces which indicate when the mixture is being exploded and when it isnot. A device-of this kind is extremely desirable as it will at once indicate-which cylinder of a multiple cylinder engine is Ordinarily when one cylinder of-a multiple cylinder engine fails to do its work, eachcylinder must be sepa: rately tested in'jorder to locate the trouble.-

- It is the main object of this invention to provide means which: will "indicate at once' Whether or not the mixture is being exr ploded within the cylinder. I accomplish T this by means of an expanding device prop-' erly supported within the cylinder, said device being responsive to variations in temperature and connected to an'indioator supported outside of the cylinder in a con 'venient' position for observation- The ex,-

panding device and the indicator constitute a thermostatwhichfltvill serve to indicate the approximate degree of heat within the cylinder so that when the mixture is explod- I ing the high degree 0t heat generated within the cylinder will be apparent from the position of the indicator.

Another object of the invention is to conveniently co bine' the thermostat with a spark plug. By this means the thermostat may be placedin position on the cylinder when the spark plug is secured in place, and may. be removed by removing the spark plug This is of-advantage for the reason, that it avoids the necessity otdrilhng' extra. holes in the engine cylinder for the purpose -It will, of course, be understood. that I may use any. suitable form of device re spending to changes in temperature and any siutable indicating means'connected thereto for showing whether or not there .is heat within the cylinder. i

Referring to the drawings:-- Figure 1 is a central. longitudinal sectional view of. a spark plug provided with a thermostat; Fig. 2 an endview of the outer end thereof; Fig. 3 a similar vie'w'of the-inner end there'- of; and Fig." 4 a detail sidfe elevation, of the detachable firing cap 'which carries the "expanding device. I

Referring to the various parts by n11,- merals, 1. designates, the base of the plug which is adapted .to' be screwed into the en'- fgine cylinden. -Within this base is mounted a porcelain insulating. core 2, said core. being formed with the enlargement 3-. A core securing and retaining gland 5v is screwed into the" outer .end of the base, and was ers 6 are interposed betweensaid gland and the enlargement of the .core, and between said enlargement and the shoulders formed within the base. Bythis means the 'insulatinsulator, said tube being open at :its ends,

the outer'end thereof projecting beyond the outer end ofthe core or insulator, said outer end being externally threaded for the reception of a binding nut 8. Extending through said tube and arranged to rotate therein is an indicator rod- 9 provided atitsupper end with an index fin'ger 10 adapted to swing around a dial 11 said dial being rigidly clamped on the tube by means of a nut 12. The indicator rod is provided with a collar 13 whichis adapted tofit within thecavity '14 formed in the inner end of the porcelain or insulating core, Said collar bears directly against the inner end offthe tube and serves to vretain in the cavity an asbestos packing '15. this means gas 7 from the engine cylinder is prevented from entering the inner end of the tube 7.

VV'ithin the'inner' end of the base is de-' tachably secured a hollow metallicca'p 1,6, said cap being formed with'the enlargement 17 at its inner-end, and with the aperture 18,

of attaching the thermostat.

said aperture being eccentric to the axis of the insulator. To the inner end of the cap is. secured a porcelain cup 19, said cupbeing formed with an opening larger than the opening through the cap, but concentric therewith. The indicator rod extends into the porcelain cup and is provided with a lateral arm 20 Within the cup is'mounted an expanding device 21,]the saiddevice be- ;ing formed of two curved bars-having different rates of expansiomsaid bars being rigidly securedat one of their'ends to the inner side of the 0111),. their other ends being free to move 'in .anare when expanded by heat. This form of expanding device is well-known,--'and the'element which expands more rapidly and'to a greater 'extentlis placed on the outer side of the other element or bar, whereby when the device as awhole is expanded by heat -itst'ree end will be seen that when -:the engine is properly firing and-its mixture properly exploded the d evice.21 willbe expanded thereby giv-' ing an indication throughfthe index finger 10 that the engine cylinder is working.

It will, of course,'be understood that when ever a cylinder fails to fireor explode the temperature will soon be reduced sufliciently to permit the device 21' to contract and there. by return the index finger to-its normal or zero position, or approximately $0, thusi'ndieating. immediately that the engine 'is not properly working; The indicator rod also forms the electrode 'and'the igniting spark is formed between-said rod and thema'rgin;

of the aperture through the cap. The terminal wire is connected to the'bindingnut 12- in the usual manner, and as the'indicator rod; and th'itllb"? are in close contact throughout the length of the tube the. current will flovi from said tube to said rod. Y

The firing cap is split longitudinally throughout its length andfrictionally-engages the interior of-the base; Itis formed with the projection 22 which is adapted to snap into an annular groove'23 formed in the interior of said base.- By thismeans the said cap is removably but firmly held within the base. y

Todetach the thermostatfrom the plug it is only'necessary to disconnect the device 21 fromthe arin'of the indicator rod and then detach the firing cap from the'base. By removing the index finger from the upper end of the indicator, the said rod-may be removed from within the tube 7. lhe index finger may be screwed or otherwise removably secured to the upper end of the'indicator rod to facilitate the removal of the rod from the tube. It is manifest that the bar what; I claim as new and 21 must be secured to an insulating part,

and-for th-at'reason the porcelain cup :l9;is

securedto the end of the firing capand the bar'2l mounted within said-cup.

It will, of course, be understood that the specific arrangement of the parts of the plug and thefthermostatmay be varied,and that any suitable form of thermostat and spark plug may be employed, and I, therefore, do not. wish to be limited to the preciseconstruction shown and described herein. It.

will also be. understood. thatv any suitable form of ployed. I It will, 0

heat indicating means] maybe em device may be. employed as a pyrometer to indicate the degrees .of heat in the combusf;

tion chamber during the explosions Having thus fully described my invention,

Letters Patentisi 1. A spark plug comprising a base, an in sulating' core extending through said -basfe,

an indi'catinglrod extending through. said .core, a' deviceresponslve to the changes in temperature connected to the inner-end of said rod, and'anindex the outer ,end of said rod.

'2; A spark plug provided with a devicere sponsive to the changes in temperature. and

desire a secur at finger connected to with an index'finger'or point, the'said'device being-adapted to, be placedwithin the engine cylinder, and thelindex fingerpoint' being adapted to lee-arranged outside .of'the engine cylinder,"and means connecting the device with the index finger.

3. A spark plug providedfwith an expan-- ,'sion device movable in respons'e'to changes in'tem'peratureand means connected to said expansiondevice j to, indicate the movements thereof;

"4. A spark. plug provided at its "inner end.

with [a movable expansion. device and with longitudinally through the l g means extending spark plug'for indicatingthe movements of the said expansion device. v

5. A spark plug consisting of a base, a

insulating core, an indicating rod extending centrally through the core, said rod serving as an electrode,-an expans ondevice connected to the nner end of'said rod and movable in response to changes of temperature to rotate said rod andan index finger-connected to the outer end; of said rod.

6. A spark plug comprising a base, an

insulating core within the base, a rotatable indicating rod extending longitudinally through the said core and serving as an electrode. a firing cap secured within the base and carrying an insulating cup at its inner end. an ex -si'on device secured within will insulating cup and connectedto t-hvc indimtiuq rod, and an index. finger connqgted to the outer end of said rod.

8. 111a (OillblllilllOll of a base or holder e be eonueeied to an engine eyiiii indicator re ean'ied by seid bese, msion device adepteei te be moved, by ehuh s in temperature and ceimec'ted to the inner end of said rod and adapted to be within the cylinler when the base is conheeted thereto and means whereby said end wili'indieete the movements of the expensien device. I

S. The combination of a base adapted to be screwed into an engine cylinder, an indicator rod extending longitudinally, through and supported by said base, an expansion device eehneeied $0 the inner end of said'rod and adapted to be within the cylinder when the base as connected thereto. and means whereby the expansion and contraction of said iievieewill be indicated through said red.

In testimony whereof I-hcreumu afiix my signatule in the pi'esenee of {we vimesses this 16th day of March 1910.

. CHARLES W. BECK. Witnesses F. .E.,M1LLBR, VM. R. DAVIS. 

